Jeju Island, South Korea, May 17, 2013 (AFP) - Kim's ten birdies left him at 14-under after day two of the tournament, one stroke ahead of overnight leader Matt Griffin (67) from Australia.
Fellow Australian Jason Norris posted his second 66 for sole possession of third place at the Pinx Golf Club, with Korea's Park Do-kyu (66) one more behind.
Kim only made it into the one billion won ($900,000) tournament as an alternate having all but lost his status on the Korean domestic tour by making just two cuts last year.
Although he has one tournament victory to his name -- the 2007 KPGA Championship -- his nine-year professional career has mostly been middle-of-the-road seasons.
The 29-year-old put his record-breaking success down to gum chewing.
"I have never done it before, but I decided to chew gum so that I would concentrate," he said. "I don't know how much I chewed, but it helped," he said in a OneAsia press release.
"I am trying not to be so stressed about the game, not to worry so much, and this definitely worked."
Kim birdied all four of the par fives and six of the par fours after making every green in regulation. He had just 25 putts, with the longest being a 20-footer on the par-four 12th.
The previous record at Pinx was a 63 scored by Korean Hur In-hoi in the third round of last year's tournament.
Griffin is chasing his second win on OneAsia and in Korea following victory in September at the Charity High1 Resort Open.
"Any time you shoot a 64 it's hard to back it up, so I was really happy with a 67 today," said Griffin, whose only bogey came at the 12th.
Defending champion Kim Bi-o (70) will have it all to do at the weekend from six under, while star attraction K.J. Choi, fresh from his appearance in The Players Championship in the United States, is better placed at eight under after shooting a 67 on Friday.
Scores after round two of the SK Telecom:
130 - Kim Chang-yoon (KOR) 68-62
131 - Matthew Griffin (AUS) 64-67
132 - Jason Norris (AUS) 66-66
133 - Park Do-kyu (KOR) 67-66
134 - Hu Mu (CHN) 66-68
135 - Lee Ki-sang (KOR) 67-68, Jin Jeong (KOR) 68-67, Kim Jae-ho (KOR) 66-69